<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml">
<head>
<meta http-equiv="Content-Type" content="text/html; charset=utf-8" />
<title>Untitled Document</title>
</head>

<body>
<form>
a = 
<input  type="text" name="textfield" id="textfield" /><br />

<input type="button" name="button" value="Submit" id="button" /><br />
a + b = 
<input type="text" name="textfield3" id="textfield3" /><br />


</form>
</body>
<script language="javascript">
var TIEN = 17000000;
elSL=document.getElementById("textfield");
elSum=document.getElementById("textfield3");
elSubmit=document.getElementById("textfield");

elSubmit.onclick=function(){
	SL=parseInt(elSL.value);
	elSum.value=SL*TIEN;
}
</script>
</html>